A Double-Blind Randomized Sham-Controlled Trial for Assessing the Effect of Repetitive Transcranial Magnetic Stimulation as an Adjunctive Treatment in Children and Adolescents with Autism Spectrum Disorder

Introduction

Autism Spectrum Disorder (ASD) is characterized by persistent deficits in social communication and interaction, coupled with restricted, repetitive behaviors. The global prevalence, estimated at 1 in 100 children according to the World Health Organization, contrasts with the 1 in 36 children reported by the Centres for Disease Control and Prevention in the United States. ASD exhibits a gender ratio of 1:4, favouring males. Associated features include cognitive delays, epilepsy, motor clumsiness, OCD, affective disorders, and ADHD. Challenges in neuropsychological tasks and executive functions further contribute to the diverse range of ASD presentations.

Repetitive Transcranial Magnetic Stimulation (rTMS) emerges as a potential therapeutic avenue for ASD, operating by delivering magnetic pulses to the brain to modulate neuroplasticity. Neuroimaging studies reveal atypical connectivity patterns in individuals with ASD, suggesting potential links between aberrant neuroplasticity and the disorder’s aetiology. Preliminary evidence supports the positive impact of rTMS on stereotyped and repetitive behaviour, social interactions, and executive functions in ASD. However, concerns about data variability, publication bias, and study quality limit the significance of these findings. Despite uncertainties regarding optimal stimulation parameters, targets, and treatment schedules, rTMS is generally considered safe and well-tolerated, with mild and temporary adverse effects.

The treatment landscape for ASD faces challenges, with limited options primarily addressing associated psychiatric conditions rather than core ASD manifestations. Nonpharmacological interventions, while promising, often require significant resources. The introduction of non-invasive neuromodulation techniques like theta-burst stimulation (TBS) and rTMS offers hope for directly impacting ASD’s core features. However, research on rTMS, specifically targeting crucial areas like the dorsomedial prefrontal cortex, remains limited, underscoring the need for further exploration. The potential of rTMS to improve outcomes for individuals on the autism spectrum hinges on continued robust research to establish clearer guidelines, understand long-term impacts, and optimize its application in ASD treatment.

Objectives

· To assess the effect of rTMS as an adjunctive treatment in children and adolescents with ASD

· To assess the improvement of social relationships and reciprocity, emotional responsiveness, speech and language communication, behaviour patterns, and sensory aspects of ASD after rTMS in children and adolescents with simultaneous Applied Behaviour Analysis Therapy.

· To assess the persistence in improvement post rTMS at 1month and 3month intervals.

· To assess safety with adverse event reporting

Methodology

The study adopts a randomized, double-blind, sham-controlled parallel group design to rigorously investigate the potential impact of repetitive transcranial magnetic stimulation (rTMS) on Autism Spectrum Disorder (ASD) symptoms. This design is chosen for its ability to minimize bias and enhance the scientific validity of the research. The study focuses on children and adolescents aged 6-15 years diagnosed with ASD, who attend the Child Psychiatry Clinic at the All India Institute of Medical Sciences in New Delhi. The sample size, determined as a minimum of 20 patients, reflects a careful consideration to ensure sufficient representation for robust statistical analysis and meaningful results.

The proposed intervention involves the application of intermittent high-frequency iTBS targeting the left dorsomedial prefrontal cortex (DMPFC). The selection of the left DMPFC as the stimulation site is grounded in its relevance to ASD pathology and neuroplasticity. This intervention will be administered over a period of three weeks, consisting of 15 sessions. This comprehensive approach is designed to explore the potential therapeutic benefits of rTMS in mitigating ASD symptoms.

Data collection procedures incorporate a set of well-established instruments to capture various aspects of ASD and treatment outcomes. The Semi-Structured Interview Sheet serves as a comprehensive tool to gather socio-demographic and clinical details related to ASD. The Edinburgh Handedness Inventory (EHI) assesses handedness, ensuring the inclusion of right-handed individuals as a criterion. The Vineland Social Maturity Scale (VSMS) is utilized to measure Social Quotient (SQ) and evaluate social capacities, providing insights into the participants’ social developmental levels. The INCLEN, a validated tool based on DSM-5

criteria, aids in diagnosing ASD. The Indian Scale for Assessment of Autism (ISAA) quantifies autism severity with high sensitivity and specificity, contributing valuable clinical information. The Repetitive Behaviour Rating Scale-R (RBS-R), a 44-item questionnaire, comprehensively assesses repetitive behaviors in ASD, offering insights into the nuanced manifestations of the disorder.

Quality control is a paramount consideration to ensure the precision of the study. Standardized instruments, including EHI and VSMS, known for their reliability and validity, contribute to the meticulous data collection process. Confidentiality is maintained through the use of alphanumeric coding to anonymize participants, and all sensitive information is securely stored.

Statistical Analysis

The plan of analysis and statistical tools encompass a meticulous approach, utilizing both intention-to-treat and per-protocol analyses. Descriptive statistics are employed for socio-demographic and clinical variables, offering a comprehensive overview. The statistical tools include mixed-model ANOVA, post-hoc tests, and careful assessment of data distribution for parametric or nonparametric analyses. These analytical strategies are chosen to provide a thorough examination of the study’s outcomes and contribute to the robustness of the findings.

Ethical Considerations

In alignment with ethical principles, the study prioritizes participant well-being and adherence to ethical standards. Written informed consent is diligently obtained, confidentiality is rigorously maintained, and participants are provided the right to withdraw without any additional cost. The study is awaiting the ethical clearance from the Institutional Ethics Committee, which would ensure the adherence to ethical guidelines and protocols. In conclusion, the study’s design, intervention, data collection methods, and ethical considerations collectively contribute to a comprehensive and methodologically sound investigation into the effects of rTMS on ASD symptoms.

Implications

The proposed research project aims to investigate the potential benefits of repetitive transcranial magnetic stimulation (rTMS) as an adjunctive treatment in children and adolescents with autism spectrum disorder (ASD). By assessing the effects of rTMS on social relationships, emotional responsiveness, speech and language communication, behaviorpatterns, and sensory aspects of ASD, the study seeks to provide empirical evidence regarding the therapeutic potential of rTMS in addressing the core symptoms of ASD. From a scientific perspective, the research project is expected to advance our understanding of neuromodulation techniques and their impact on neuroplasticity in individuals with ASD.The study has the potential to contribute to the broader scientific understanding of neurodevelopmental disorders and the role of non-invasive neuromodulation techniques in their management. Additionally, the student conducting the research is anticipated to gain valuable insights into the design and implementation of clinical trials, data collection and analysis, and the interpretation of findings within the context of neuroscientific and psychiatric research. This hands-on experience will contribute to the student’s academic and professional development and add to the body of knowledge in the field of neuropsychiatry and neurology.